OK, here's a different, but related, question. If the hohenzollerns become extinct AFTER they become kings of prussia, which house do their titles pass too. I know of a number of agreements the hohenzollerns made with their neighbours saying that if one house went extinct, the other would get their lands (off the top of my head I seem to remember this is how they got their half of pomerania and their claim to silesia), but given that the hohenzollerns made many such agreements, which one would they actually follow through on???